Metal razor blades, including single edge industrial blades, have been in existence for many years. Generally, a metal razor blade consists of a metal blade edge, a metal back and a central slot. The central slot allows the razor blades to be held in a safety scraper or stacked together in a dispenser. Metal razor blades often have limited value because they are too sharp for many applications such as label scraping on painted surfaces or glass surfaces. Additionally, metal razor blades may chip during use, leaving behind a small piece of sharp hardened steel. For this reason, metal razor blades cannot be used in applications where a small piece of sharp steel would be problematic in field use or dangerous in field conditions, e.g. food preparation.
Because of the above limitations of metal razor blades, many field uses such as label removal and food preparation currently rely on all-plastic razor blades. The edge of the all-plastic blade is not as sharp or hard as a metal blade and does not dig into or damage a paint cured surface. The consequences of a plastic chip being left from an all-plastic blade are less likely and, if left behind, is much less severe compared to a sharp metal chip. Additionally, all-plastic razor blades have a much lower risk of cut injuries than steel razor blades.
Nevertheless, the all-plastic razor blades themselves are limited in use because they lack the strength and sharpness of metal razor blades. One particular problem of all-plastic razor blades is that they are more likely to bend during use. Once bent, the all-plastic razor blade no longer functions properly.